I would highly recommend Look To Windward. However, up until now, it wasn't my absolute favorite book by Banks. That honor probably goes to Inversions. It took some time for the story to really get going. There were also a few too many jumps in time and perspective. I felt that these detracted a bit from the momentum of the narrative. But, once the reader finally figures out what's at stake, it becomes a tense, unpredictable, and thoughtful book. In fact, it's almost philosophical. It is set in a complex and interesting milieu, namely the Culture universe. Oh, and let's not forget the great epilogue! It really ties things up nicely and leaves the reader with a lot to think about.